The interaction of light with a cluster of gyrotropic spherical particles is studied in view of a miniaturized Faraday rotator. The electromagnetic fields are expanded in terms of the vector multipole fields and the expansion of the scattered field is related to that of the incident field. An incident linearly polarized light with polarization azimuth $\psi$ becomes elliptically polarized upon scattering from the cluster. The polarization azimuth rotation and ellipticity angle variation are almost sinusoidal functions of $2\psi$. With planar disordered clusters of bismuth-substituted yttrium iron garnet nanoparticles of radius 50 nm, polarization rotations about $\pm 4^{\circ }$ are achievable.

中文翻译：

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磁光纳米粒子聚集体的法拉第旋转光谱

鉴于小型化的法拉第转子，研究了光与一团回旋球形颗粒之间的相互作用。电磁场根据矢量多极场而扩展，散射场的扩展与入射场的扩展有关。具有偏振方位角的入射线性偏振光$\psi$当从团簇散射时，它变成椭圆极化。极化角旋转和椭圆率角变化几乎是正弦函数$\mathrm{2个}\psi$。铋取代钇铁石榴石纳米粒子的平面无序簇半径为50 nm，极化旋转约为$\pm 4^{\circ }$ 是可以实现的。